Short-keeled variants


Fin and spade Fin and skeg


These boats began to appear when the continual shortening of the classic yacht keel had moved the rudder too close to the centre of lateral resistance for it to work properly. The logical answer was to separate the rudder from the keel and hang it right aft for maximum leverage. The original ‘short’ keels are long by modern standards; they also remain moulded into the hull rather than being bolted on, conferring handling characteristics more like a classic yacht than later short-keeled variants. The rudder is securely hung from a skeg which, like the keel, is moulded into the hull, while the forefoot shows signs of the classics from whence it came. Such yachts often deliver a wholesome compromise between precise steering at sea, comfort, and athletic turning in harbour. Their general stability ratings can be very promising, but, like most of the more recent hull forms, they tend to lie beam-on to the wind if left to their own devices.


The logical development from the fin-and-skeg form was to make the hull into a lighter displacement ‘canoe body’ type with a bolt-on keel. The keel could now be shorter and thus potentially more efficient to windward, especially when complemented by a deep, hydrodynamic ‘spade’ rudder. A spade rudder is unsupported except for the stock with its through-hull bearings. Although these rudders have long since overcome their structural teething problems, they remain more vulnerable than rudders which carry bearings nearer to or at their lower ends. Fin-and-spade craft are typically beamier than their predecessors, with high internal volume. They should perform well in terms of speed and pointing, but often prove less comfortable in a seaway when the virtually non-existent forefoot pounds upwind. Many – but not all – such cruisers exhibit difficult steering characteristics in gusty weather, leading to a serious imbalance at high angles of heel if wide beam is carried a long way aft to create the space demanded by stern cabins. The salient keel and rudder, as well as the propeller which must inevitably be hung on a bracket, are all vulnerable to picking up ropes and other obstructions that would slide off a long-keeled hull with a stern-hung rudder and propeller aperture. The pay-off is a roomy craft which can be a delight to steer astern.


The bilge keeler


Twin bilge keels as an alternative to a single fin or the rarer centreboard were developed in the mid-20th century in a successful attempt to reduce draught while retaining reasonable sailing ability and seaworthiness. The bilge- keeler has the advantage of being able to sit upright on the bottom. This means she can dry out unsupported on the tide. The price for this huge benefit is some cost in pointing ability and, in some cases, ultimate stability, but since most bilge-keelers are not used for deep-ocean voyaging, storm survival is an unlikely issue. At sea, their generally moderate characteristics mean that most steer without problems. Rudders are well aft and usually protected by a skeg.


10 | MANUAL OF SEAMANSHIP


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